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1 – 10 of 184Sabeeh Lafta Farhan, Dhirgham Alobaydi, Daniel Anton and Zuhair Nasar
This paper is intended to assess the developments conducted on the master plan of Old Najaf, mainly in three areas: the Imam Ali Holy Shrine and its surroundings, the Great Market…
Abstract
Purpose
This paper is intended to assess the developments conducted on the master plan of Old Najaf, mainly in three areas: the Imam Ali Holy Shrine and its surroundings, the Great Market Area and the location of the Town of Visitors.
Design/methodology/approach
In order to analyse the implementation of the transformation phases in Old Najaf, the Strengths, Weaknesses, Opportunities, and Threats (SWOT) technique was used to identify and organise the strengths, weaknesses, opportunities and threats related to the examined case study of the city's historic centre. At the first stage, all available data (photographs, maps, documents and reports) were collected from different sources, including previous studies by governmental institutions, departments and agencies. Ultimately, the SWOT analysis was used for each identified phase in the morphological evolution of the historic centre. This can offer an opportunity to observe the implications of urban planning practices in Old Najaf from the mid-20th century to the present day. In order to identify the well-organised urban design practices and appropriate strategies, the implemented studies and projects were examined by the four factors of the SWOT analysis.
Findings
The current results have revealed important urban transformations, already made and/or ongoing, of those aforementioned three main areas, which imply a great loss of the city's traditional character and urban heritage. Further, the environmental and socio-economic issues should be involved in the analysis to evaluate how they have influenced the current outcomes of Old Najaf in relation to the urban configuration and orientation.
Originality/value
The rich cultural and architectural heritage of Al-Najaf historic centre is dramatically neglected and seriously threatened to be lost. Hence, conservation on both tangible and intangible levels is urgently needed. It is the first paper which focussed on this problem and tries to learn from the British Conservation Experiences in this field.
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Aurel-Sorin Lup, Gabriela Ciuprina, Daniel Ioan, Anton Duca, Alexandra Nicoloiu and Dan Vasilache
The purpose of this paper is to propose a physics-aware algorithm to obtain radio frequency (RF)-reduced models of micro-electromechanical systems (MEMS) switches and show how…
Abstract
Purpose
The purpose of this paper is to propose a physics-aware algorithm to obtain radio frequency (RF)-reduced models of micro-electromechanical systems (MEMS) switches and show how, together with multiphysics macromodels, they can be realized as circuits that include both lumped and distributed parameters.
Design/methodology/approach
The macromodels are extracted with a robust procedure from the solution of Maxwell’s equations with electromagnetic circuit element (ECE) boundary conditions. The reduced model is extracted from the simulations of three electromagnetic field problems, in full-wave regime, that correspond to three configurations: signal lines alone, switch in the up and down positions.
Findings
The technique is exemplified for shunt switches, but it can be extended for lateral switches. Moreover, the algorithm is able take frequency dependence into account both for the signal lines and for the switch model. For the later, the order of the model is increased until a specified accuracy is achieved.
Originality/value
The use of ECE as boundary conditions for the RF simulation of MEMS switches has the advantage that the definition of ports is unambiguous and robust as the ports are clearly defined. The extraction approach has the advantage that the simplified model keeps the basic phenomena, i.e. the propagation of the signal along the lines. As the macromodel is realized with a netlist that uses transmission lines models, the lines’ extension is natural. The frequency dependence can be included in the model, if needed.
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Ruben Quirinus Vrolijk, Fiona Measham, Adrià Quesada, Anton Luf, Dominique Schori, Sarah Radley, Dean Acreman, Josie Smith, Marko Verdenik, Daniel Martins, Mar Cunha, Carlos J. Paulos, Ilaria Fineschi Piccinin, Enrico Gerace, Alexandra Karden, Raoul Pieter Joost Koning, Laura Alexandra Smit-Rigter and Mireia Ventura
The 3,4-methylenedioxymetamphetamine (MDMA) content in ecstasy tablets has increased enormously throughout Europe across the past decade. This study aims to determine whether this…
Abstract
Purpose
The 3,4-methylenedioxymetamphetamine (MDMA) content in ecstasy tablets has increased enormously throughout Europe across the past decade. This study aims to determine whether this is caused by the production of “stronger” tablets (more mg MDMA per mg of tablet), or if tablets have simply been getting larger and heavier (more mg of tablet in total).
Design/methodology/approach
A data set of 31,716 ecstasy tablets obtained in 2012–2021 by 10 members of the Trans European Drug Information (TEDI) network was analysed.
Findings
The MDMA mass fraction in ecstasy tablets has remained virtually unchanged over the past 10 years, with increased MDMA contents being attributed almost exclusively to increased tablet weight. These trends seem to be uniform across Europe, despite varying sampling and analytical techniques being used by the TEDI participants. The study also shows that while tablet weight correlates perfectly with MDMA content on a yearly basis, wide variations in the MDMA mass fraction make such relations irrelevant for determining the MDMA content of individual tablets.
Research limitations/implications
These results provide new opportunities for harm reduction, given that size is a tangible and apparently accurate characteristic to emphasise that one tablet does not simply equate to one dose. This is particularly useful for harm reduction services without the resources for in-house quantification of large numbers of ecstasy tablets, although the results of this study also show that chemical analysis remains crucial for accurate personalised harm reduction.
Originality/value
The findings are both new and pertinent, providing a novel insight into the market dynamics of ecstasy tablet production at a transnational level.
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Gabriela Ciuprina, Daniel Ioan, Aurel-Sorin Lup, Luis Miguel Silveira, Anton Duca and Michael Kraft
This paper proposes an algorithm for the extraction of reduced order models of MEMS switches, based on using a physics aware simplification technique.
Abstract
Purpose
This paper proposes an algorithm for the extraction of reduced order models of MEMS switches, based on using a physics aware simplification technique.
Design/methodology/approach
The reduced model is built progressively by increasing the complexity of the physical model. The approach starts with static analyses and continues with dynamic ones. Physical phenomena are introduced sequentially in the reduced model whose order is increased until accuracy, computed by assessing forces that are kept in the reduced model, is acceptable.
Findings
The technique is exemplified for RF-MEMS switches, but it can be extended for any device where physical phenomena can be included one by one, in a hierarchy of models. The extraction technique is based on analogies that are carried out for both the multiphysics and the full-wave electromagnetic phenomena and their couplings. In the final model, the multiphysics electromechanical phenomena is reduced to a system with lumped components with nonlinear elastic and damping forces, coupled with a system with distributed and lumped components which represents the reduced model of the RF electromagnetic phenomena.
Originality/value
Contrary to the order reduction by projection methods, this approach has the advantage that the simplified model can be easily understood, the equations and variables have significance for the user and the algorithm starts with a model of minimal order, which is increased until the approximation error is acceptable. The novelty of the proposed method is that, being tailored to a specific application, it is able to keep physical interpretation inside the reduced model. This is the reason why, the obtained model has an extremely low order, much lower than the one achievable with general state-of-the-art procedures.
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Timothy Oluwatosin Olawumi and Daniel W.M. Chan
The increasing urbanization of the built environment has bolstered the need to promote green Building Information Modeling (BIM) initiative in new construction projects and the…
Abstract
Purpose
The increasing urbanization of the built environment has bolstered the need to promote green Building Information Modeling (BIM) initiative in new construction projects and the rehabilitation of old premises. This study aims to explore and examine the key benefits of the implementation of BIM and sustainability practices in the built environment.
Design/methodology/approach
The study gathered the worldwide perceptions of 220 survey participants from 21 countries which were analyzed using descriptive and inferential analytical methods. The identified individual benefits of green BIM were further categorized into their underlying clusters using factor analysis.
Findings
The key benefits are related to enhancing project efficiency and productivity, ensuring real-time sustainable design and multi-design alternatives, facilitating the selection of sustainable materials and components, together with reducing material wastage and project’s environmental impact, among others. The study analyzed and compared the perceptions of the diverse groups of the respondents as well.
Practical implications
Effective blueprints and insightful recommendations for enhancing the various stakeholders’ capacities to implement green BIM in their construction projects were put forward to achieve the aim of sustainable smart urbanization.
Originality/value
The study identified salient benefits of the adoption of BIM and sustainability practices. The proper integration of these concepts and the execution of the recommended useful strategies by construction stakeholders, policymakers and local authorities will enable the built environment to reap the gains of its implementation.
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Carine Fournier and Rémy Knafou
This chapter demonstrates that despite an unfavorable disciplinary climate for new academic subjects in France, tourism found its place in the French geographical scene almost 40…
Abstract
This chapter demonstrates that despite an unfavorable disciplinary climate for new academic subjects in France, tourism found its place in the French geographical scene almost 40 years ago. The first part traces the history of tourism in French geography until the epistemological turn due to the research laboratory MIT in the mid-1990s. It also focuses on the absence of knowledge of the Anglo-American literature and of multidisciplinarity in French research on tourism. The second part focuses on the valorization of tourism geography research in France, emphasizing the development of multidisciplinarity since the early 2000s, including the creation of a multi-disciplinary tourism laboratory and two journals. The chapter concludes reflecting on the possibility of a science of tourism.
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Timothy O. Olawumi and Daniel W.M. Chan
The purpose of this paper is to explore building information modeling (BIM) implementation and practices in developed economies by developing a benchmarking model that will…
Abstract
Purpose
The purpose of this paper is to explore building information modeling (BIM) implementation and practices in developed economies by developing a benchmarking model that will enhance BIM adoption and implementation in developing countries.
Design/methodology/approach
The research design adopted a qualitative approach which includes the desktop review of the extant literature as well as case study reviews of ten BIM projects using an explanatory case study technique to form the foundation upon which the study proposed the model. The moving basis heuristics technique was adopted to develop the scoring system.
Findings
The BIM benchmarking model and assessment template were developed which consisted of three-level concepts modeled to aid project organizations and project team in developing countries to assess and score the level of improvement and implementation of BIM in a project. A desktop review of BIM projects in developed countries demonstrated the significant improvements and benefits possible through the implementation of the established BIM benchmarking model.
Practical implications
The assessment template in conjunction with the benchmarking model is useful for a comparative evaluation of similar BIM projects and benchmarking purposes. The study also discussed how current findings extends and contradicts previous findings.
Originality/value
The findings have provided policymakers, construction stakeholders and professional bodies in the construction industry in developing countries with valuable insights and counter-intuitive perspective that could facilitate the uptake of BIM in construction projects.
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Daniel Watzenig, Gerald Steiner, Anton Fuchs, Hubert Zangl and Bernhard Brandstätter
The investigation of the influence of the modeling error on the solution of the inverse problem given uncertain measured data in electrical capacitance tomography (ECT).
Abstract
Purpose
The investigation of the influence of the modeling error on the solution of the inverse problem given uncertain measured data in electrical capacitance tomography (ECT).
Design/methodology/approach
The solution of the nonlinear inverse problem in ECT and hence, the obtainable accuracy of the reconstruction result, highly depends on the numerical modeling of the forward map and on the required regularization. The inherent discretization error propagates through the forward map, the solution of the inverse problem, the subsequent calculation of process parameters and properties and may lead to a substantial estimation error. Within this work different finite element meshes are compared in terms of obtainable reconstruction accuracy. In order to characterize the reconstruction results, two error measures are introduced, a relative integral error and the relative error in material fraction. In addition, the influence of the measurement noise given different meshes is investigated from the statistical point of view using repeated measurements.
Findings
The modeling error, the degree of regularization, and measurement uncertainties are the determining and limiting factors for the obtainable reconstruction accuracy of electrical tomography systems. The impact of these key influence factors on the calculation of process properties given both synthetic as well as measured data is quantified. Practical implications – The obtained results show that especially for measured data, the variability in calculated parameters strongly depends on the efforts put on the forward modeling, i.e. on an appropriate finite element mesh size. Hence, an investigation of the modeling error is highly recommended when real‐world tomography problems have to be solved.
Originality/value
The results presented in this work clearly show how the modeling error as well as inherent measurement uncertainties influence the solution of the inverse problem and the posterior calculation of certain parameters like void fraction in process tomography.
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In this paper, after an elucidation of several central concepts of the topic, the author focuses on the sales channels in tourism and clarifies the role retailers play in the…
Abstract
In this paper, after an elucidation of several central concepts of the topic, the author focuses on the sales channels in tourism and clarifies the role retailers play in the market. He shows that the existence of institutional travel retailers is generally based on transaction costs, and that thanks to the automation the level of dependence on transaction costs can be reduced. This thesis induces the question to what extent the retailers' performances can be automated. In answer to this question the author creates a list of criteria including the following aspects; the general and occasional suitability of retail products (e g tickets, travel packages), the availability of technical equipment and information necessary for the automation at the points of sale and in the households (buyers), the level of complexity and acceptance regarding the handling of automated travel services. The paper comes to the conclusion that the automation of travel services will probably be used mainly by business travelers, whereas private customers will more likely keep their affinity for conventional retailers.
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Ifeoluwa Benjamin Oluleye, Abiodun Kolawole Oyetunji, Michael Ayodele Olukolajo and Daniel W.M. Chan
Building information modelling (BIM) is a novel technological advancement in the built environment. Despite the potentials of BIM, its adoption and implementation are undermined…
Abstract
Purpose
Building information modelling (BIM) is a novel technological advancement in the built environment. Despite the potentials of BIM, its adoption and implementation are undermined in facility management (FM) operations. This might be because of limited information on the critical success factors (CSFs) that can enhance its adoption. The study aims to integrate building information modelling to improve facility management operation by adopting fuzzy synthetic approach for evaluating the critical success factors.
Design/methodology/approach
Data for the study were sourced from practising and registered facility managers within Lagos metropolis, Nigeria. The data collected were analysed using a combination of methods which include mean item score, factor analysis and fuzzy synthetic evaluation (FSE).
Findings
The factor analysis results showed that six underlying groups of CSFs would enhance the effective adoption of BIM in facility operations. The FSE results showed that out of the six groups, the three topmost important CSF grouping (CSFG) in the decision rule would enhance the effectiveness of BIM adoption for FM operations.
Practical implications
The result of this study provides a credible road map for facility managers, policymakers and other stakeholders in FM operations on the CSFs and CSFG required for the adoption of BIM.
Originality/value
Previous studies that aimed at integrating BIM into FM are limited. Hence, this study provides a broad perspective on the CSF required for BIM adoption and implementation in FM operations using the FSE approach.
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